1. Field of the Invention
The field of the present invention is related to the transmission of data between a source device and a target device. More particularly, the present invention relates to the determination of a capacity limitation associated with the communication connection between a source device which is the source of a data transmission and a target device which is the target of a data transmission. Even more particularly, the present invention relates to determining the actual data transmission capacity of the communication connection between the source device and the target device.
2. Description of the Related Art
Data transmission from a source device to a target device has become very common place for many people today. For example, sending and receiving e-mail is accomplished by transferring data from the first source device, the computer of the sender of the e-mail, to a network computer, the first target device. The first target device is also the second source device, because it then transmits the data to a second target device. The network computers continue to transmit the data between themselves until, finally, the last network computer transmits the data to the last target device, the computer of the receiver of the e-mail.
People who work in offices with a computer on an internal network have basically the same setup. However, there are usually fewer computers related to the transmission of data. A person using a computer connected to a small network, for example, whom saves a word processor document on a network drive rather than his computer's internal hard drive, transmits data directly from his source computer to a network hard drive, the target device. In each transmission of data, a coordination must take place between the source device and the target device such that the data that is received by the target device is exactly the same as the data transmitted from the source device.
To address this problem, various methods exist in the prior art, none of which are completely satisfactory. For example, one method comprises attaching coded data to each transmission such that when a transmission received by the target device does not exactly match the transmission initiated by the source device, the target device recognizes the errors and requests a retransmission of the data.
Although the retransmission of data is desirable in the sense that it improves the accuracy of data transmissions from a source device to a target device, retransmission of data is not desirable in the sense that it increases the amount of time required to complete a data transmission. Further, a reoccurring retransmission is a significant problem.
In another example of the prior art, there was an attempt to resolve this problem by setting the data transmission capacity at the capacity of the source computer or the target computer, whichever was lowest. The connection between the computers was not normally considered a limiting factor, because the cable used to connect the computers is usually rated for a data transmission capacity at least in excess of the data transmission capacity of the lowest capacity computer. In actual applications, however, retransmissions still occur and still cost network users time and money.
It is desirable, therefore, to anticipate the problems that reoccur during transmission of data that trigger a retransmission and reduce the number of retransmissions by correcting or working around the problems.
A further problem with the existing art is the inability to adequately test and troubleshoot a computer network connection. For an existing connection, if the cable used is short, accessible, and the apparent source of a problem, the cable is simply replaced in the hope that the problem is resolved. In big networks integrated into large buildings or in small networks residing in a residential home, the cable is not as accessible. Therefore, the cable is tested. A prevalent practice for testing cables involves checking the continuity of each wire within the cable. Although tests have the ability to find major defects in a network connection, they are not accurate enough to determine minor defects, such as defects in the insulation of the communication connection. In addition, the practice does not find alternative solutions to replacing the network cable when such replacement would involve a significant cost and effort. Therefore, it is desirable to find a way to maximize the transmission capacity of a damaged or defective network connection cable.
Another prevalent practice is to carry a laptop around to each existing network connection and test the connection by trying to access data on a network drive. This practice is also inadequate, because it tests only for significant deficiencies in the data transmission capacity and does not offer methods to increase the data transmission capacity without pulling a new cable.